Apple’s remarkable run of earnings growth came to a halt in the past fiscal year as the company’s annual profit fell for the first time in more than a decade. An increasingly competitive mobile market squeezed the profitability of its flagship products, the iPhone and iPad, raising questions about whether Apple’s best days are behind it.

Apple sought to dispel such notions during this past holiday quarter. It rolled out two new versions of its iPhone, the first time it has launched more than one new model of its smartphone at the same time, and refreshed its iPad line-up.

New products will help drive sales, but the changing smartphone landscape is pressuring Apple’s bottom line. Much of the growth now comes from emerging markets, where low-cost alternatives to Apple’s high-end products are more popular. What’s more, the company needs to spend heavily on marketing to keep fueling demand for its products amid a flurry of new smartphones from competitors.

Wall Street will be watching to see if those factors weighed on Apple. The average estimate from analysts is for net income of $12.68 billion, about 3% lower than a year ago. Profit is expected to decline even though revenue is projected to rise 5% to $57.46 billion — toward the high end of Apple’s forecast of $55 billion to $58 billion.

Apple will report earnings after the market closes Monday and hold a conference call at 5 p.m. ET. The Journal is live blogging the call here; here are some key themes to watch:

How Margins Are Holding Up: The most closely watched numbers will be Apple’s gross margin in the December quarter and its forecast for the current quarter. Gross margin — the percentage of revenue that remains after manufacturing costs — is viewed as the purest snapshot of Apple’s profitability. For the December quarter, Apple forecast gross margin of 36.5% to 37.5%, with analysts predicting that it will come in at the high end of that range. Just two years ago, Apple’s gross margins were routinely above 40%, hitting a high of 47.4% in the March quarter of 2012.

Sales of the Flagship Product: The iPhone remains Apple’s most important product, accounting for more than half of its revenue. Apple launched the iPhone 5S and 5C in September, with a new emphasis on foreign markets. For the first time, Apple introduced the new phones in China without a delay; it also inked a long-awaited deal with Japan’s largest carrier, NTT Docomo. Analysts are forecasting sales of about 55 million iPhones in the quarter, or about a 15% increase from the year-ago period. The figures are not expected to include sales to China Mobile, the world’s largest carrier, which started selling the iPhone earlier this month.

The Cash Fight With Icahn: The activist investor Carl Icahn has ramped up his campaign for Apple to reduce its cash hoard by repurchasing more shares. Icahn, who says he has acquired $3.6 billion in Apple shares, wants a shareholder vote on a proposal for Apple to buy an additional $50 billion in shares by September — beyond the $60 billion Apple already has pledged to repurchase. So far, the company has rebuffed Icahn’s proposals. Investors will be listening to hear if the company offers any additional plans for Apple’s cash pile – $147 billion and growing — to keep Icahn happy.

Business in China: CEO Tim Cook said signing up China Mobile, which has more than 700 million subscribers, was a watershed moment for the company. It bolsters Apple’s position in the world’s largest smartphone market, where it lags behind rivals. Apple has not spoken about the potential impact of the China Mobile deal, but analysts are forecasting that it could result in an additional 15 million iPhones for the Chinese market this year. While announcing the China Mobile deal, Cook also said Apple sold more iPhones in Greater China, which includes Hong Kong and Taiwan, in the December quarter than ever before. Investors are anxious to see the impact on revenue in Greater China, Apple’s third-largest region for sales.

Any Word on New Products: Apple has said that 2014 will be a big year, a declaration that many take as a sign that the company will move into a new product segment. It has been four years since Apple introduced a major new product, the iPad, and speculation is building that the company is preparing something new such as a watch or a television. Will Apple executives spill the beans on what it has in the pipeline? Don’t hold your breath.